var img_bola = new Image();
img_bola.src = "images/bola.gif";
var img_barra = new Image();
img_barra.src = "images/barra.png";
var img_block = new Image();
img_block.src = "images/block.png";
var img_fresa = new Image();
img_fresa.src = "images/fresa.png";
var img_manzana = new Image();
img_manzana.src = "images/manzana.png";
var img_estrella = new Image();
img_estrella.src = "images/estrella.png";